[TriLUG] disk-wiping tool?

[Joseph Tate]

Basically because sophisticated detectors can tell the difference 
between a zero overwritten with a zero and a one that was overwritten by 
a zero.  If you want to know more detail, you'll have to google, or 
search ACM.

Neil Roeth wrote:
> On Nov 13, Tanner Lovelace (lovelace at wayfarer.org) wrote:
>  > Andrew Perrin wrote:
>  > > Try booting to anything, then doing:
>  > > 
>  > > dd if=/dev/random of=/dev/hd{x}
>  > > 
>  > > where {x} is the drive you want to wipe.
>  > > 
>  > > ap
>  > > 
>  > 
>  > One small correction.  For this you should probably use /dev/urandom
>  > instead because /dev/random will block if there isn't enough randomness
>  > in the random pool.  /dev/urandom will use the randomness in the pool
>  > to generate a pseudo-random sequence and will therefore never block.
>  > So, if you want to get done in a timely fashion, use /dev/urandom
>  > instead of /dev/random when overwriting your harddrive.
> 
> Is /dev/urandom preferable to /dev/zero?  If so, why?
>